First, you are dealing with minimum wage employees who probably don't give a shit. If Pizza Hut paid wages competent people would accept, no one would buy their pies because the prices would be too outrageous for most people.
A genius may have written the program for online pizza orders, but along the way he forgot it would ultimately be used by idiots.
I would write a letter to Corporate explaining exactly what happened, including a copy of the receipt. An email might work, but you have not been satisfied with their electronic commerce already so I would go another route. A letter will really get the attention of the suits.
Don't make any demands. Don't be a wise-ass. Simply explain your experience and describe how it made you feel about their company. You might also mention that you shared your story with many friends and acquaintances (us) who informed you that Papa Johns does a much better job of filling online orders. That will get their attention, too.
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